S. Suarez et al., MOLECULAR STUDY OF THE GERMINAL REVERSIONS INDUCED AT THE WHITE-IVORYLOCUS IN DROSOPHILA-MELANOGASTER, Mutagenesis, 11(6), 1996, pp. 559-563
The white-ivory somatic mutation test of Drosophila melanogaster is ba
sed on the reversion of the X-linked eye colour recessive mutation whi
te-ivory to wild-type, Although the exact mechanism of white-ivory rev
ersion is not quite understood, it has been suggested that such revers
ion, both in somatic and germ-line cells, could be due to the precise
excision of the tandemly duplicated 2.96 kb DNA fragment characteristi
c of the,white-ivory mutation, We have attempted to confirm this hypot
hesis analysing, at the molecular level, different germinal revertants
induced by chemical treatment with three well known alkylating agents
: ethyl methanesulphonate, methyl methanesulphonate and N-nitroso-N-et
hylurea. The molecular analysis of these germ-line revertants, using S
outhern blot hybridization and polymerase chain reaction techniques, s
hows that such reversions are associated with the deletion of the 2.96
kb tandemly duplicated DNA sequence of the white-ivory locus.